The roles of metal centers in biology will be explored using resonance Raman spectroscopy as a structure probe. The focus will be on iron and copper proteins, on zinc proteins substituted with cobalt, and on vitamin B12. The technique permits monitoring of vibrational modes associated with the binding site, and is sensitive to alterations in structure associated with biochemical function. BIBLIOGRAPHIC REFERENCES: "Resonance Raman Spectroscopic Evidence for Structural Variation Among Bacterial Ferrodoxin, HiPIP and Fe4S4(SCH2Ph)4 2-11", S-P.W. Tang, T.G. Spiro, C. Antanaitis, T.H. Moss, R.H. Holm, T. Herkowitz & L.E. Mortensen, Biochem. Biophys. Res. Commun., 62, 1-6 (1975). "Raman and Infrared Spectra of Hf(BH4)4 and HF(BD4)4 Evidence for HF-B Bonding", T.A. Keiderling, W.T. Wozniak, R.S. Gay, D. Jurkowitz, E.R. Bernstein, S.J. Lippard & T.G. Spiro, Inorg. Chem., 14, 576-579 (1975).